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This is used in NWN but is a little weak - due to Spell Focus you can get up to 16 + characters relevant ability score already. May have to tune
Therefore we've upped it to include the relevant spell focus feats, meaning you could get 26 + caster ability score boosting the power somewhat.
Spellcraft Requirement
From D&D source it is essentially the DC to develop the spell minus 20 (for take 20) so DC 46 spellcraft check needs a 26 spellcraft requirement.
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